Lightweight linear motor and linear compressor

Abstract

An upper outer soft magnet and an inner soft magnet of the linear motor are in a circular ring shape, the cross section of the left outer soft magnet and the cross section of the right outer soft magnet are in a C shape with an opening facing the upper outer soft magnet, and the upper outer soft magnet, the left outer soft magnet, the right outer soft magnet and the inner soft magnet jointly form a C-shaped stator component. A cavity defined by the upper outer soft magnet, the left outer soft magnet and the right outer soft magnet serves as a placement space of a motor winding, and an external coil structure of the stator component is formed. The C-shaped motor structure has the form of a long magnet yoke, short magnetic steel and an external coil, and high specific thrust and high motor efficiency under the limitation of axial and radial sizes of the motor are realized; a single high-strength columnar machining spring is adopted as a supporting structure of a motor rotor component, a traditional plate spring assembly or a spiral coil spring assembly is replaced, the axial size and the radial size of the compressor are further greatly reduced, radial flexible self-adjustment of the rotor component is achieved, the friction force between a compression piston and an air cylinder is reduced, abrasion is reduced, and the service life of the compressor is prolonged.

Description

Technical Field

[0001] The invention relates to a linear motor, in particular to a lightweight linear motor and a linear compressor type refrigerator using the linear motor. Background Art

[0002] In the prior art, the linear compressor of the cryogenic refrigerator is mainly composed of a linear motor component (including a motor stator component and a motor mover component), a mover support structure component and a compression cylinder. Generally, the motor stator component adopts a "wedge-shaped" motor structure with a built-in motor winding, and the support structure of the motor mover component adopts a leaf spring assembly or a coil spring assembly.

[0003] The existing linear compressor is composed of a linear motor stator component A, a linear motor mover component B, a leaf spring assembly C, and a compression cylinder D (see Figure 1 ). The motor stator components in existing linear compressors usually adopt a "wedge-shaped" motor structure, which has a complex structure, is difficult to process, has a large size, has limited winding space for the motor winding, and is difficult to design for lightweight.

[0004] When the existing linear compressor is working, under the input of AC current, the "wedge-shaped" linear motor stator component A forms a motor magnetic circuit, providing alternating electromagnetic force for the motor mover component B, thereby driving the compressor piston in the mover component to achieve axial reciprocating linear motion, forming an alternating pressure wave in the compression cylinder D, and finally transmitting it to the expander end in the refrigerator, pushing the expeller to expand and do work to produce a refrigeration effect.

[0005] In the prior art, the motor rotor component is usually composed of an upper leaf spring C1, an inner spacer C2, an outer spacer C3, and a lower leaf spring C4 (see Figure 2 ). The leaf spring assembly C is connected to the linear motor mover component B to provide axial stiffness and radial support for the mover component. This type of motor mover component is usually supported by a leaf spring assembly composed of multiple parts, which requires high assembly precision and has a complex structure. In addition, the size of the parts cannot be significantly reduced under existing processes. At the same time, the traditional leaf spring assembly support structure cannot be adaptively adjusted in the radial direction. When the piston and the cylinder come into contact due to process and other reasons, the compression piston wears out. Due to the large non-adjustable friction, the compressor fails faster and the service life of the refrigerator is reduced. The traditional support structure also includes a coil spring assembly. When the coil spring is compressed, there is severe buckling, which results in poor linearity of movement and low radial stiffness. The component structure with fixed ends is complex and has poor reliability.

[0006] On the other hand, existing linear compressors use a large number of components, complex processes, low production efficiency, and low product yield and performance consistency, which increases costs and is not conducive to mass production. Summary of the invention

[0007] The purpose of the present invention is to provide a lightweight linear motor and linear compressor, and the overall technical solution is as follows: the motor stator component adopts a "C"-shaped structure, that is, a long magnetic yoke, a short magnetic steel, and an external coil, which provides a larger winding space for the motor winding, so that the motor magnetic circuit has a larger specific thrust, and achieves a large cooling capacity refrigeration performance under a miniaturized refrigerator structure. The motor mover component is supported by a single high-strength cylindrical machine-added spring to achieve radial flexible self-adjustment of the compression piston in the cylinder, reduce the probability of piston wear, and effectively increase the service life of the compressor. At the same time, the supporting part has a simple structure, greatly reduces the axial length and radial height of the compressor, is easy to achieve lightweight, and has a small number of components, low assembly difficulty, high yield rate and production efficiency, which further reduces the manufacturing cost of the linear compressor.

[0008] Specifically, the technical solution of the present invention is:

[0009] A lightweight linear motor comprises a stator component 1, a mover component 2 and a mover support structure 3, wherein the stator component 1 comprises an upper outer soft magnet 11, left and right outer soft magnets 12, a motor winding 13 and an inner soft magnet 14, the mover component 2 comprises a magnetic tile 21 and a compression piston 22, and the support structure 3 comprises a columnar machine spring 31, a piston screw 32, a spring pin 33 and a sealing end cover 34; wherein:

[0010] The upper outer soft magnet 11 and the inner soft magnet 14 are in a circular ring shape, and the cross section of the left and right outer soft magnets 12 is in a C shape with the opening facing the upper outer soft magnet 11. The upper outer soft magnet 11, the left and right outer soft magnets 12, and the inner soft magnet 14 together constitute a "C"-shaped stator component 1. Among them, the left and right outer soft magnets 12 are axially symmetrical structures, and winding wire grooves are opened on the radial end faces to facilitate the motor lead-out; the cylindrical surface of the inner soft magnet 14 is cut with a number of straight line grooves along the axial direction, and the wire grooves are evenly arranged, which can effectively reduce the eddy current loss in the motor magnetic circuit; the cavity surrounded by the upper outer soft magnet 11 and the left and right outer soft magnets 12 is the placement space of the motor winding 13. Compared with the traditional structure, it is an external coil, and its long rectangular cavity structure can not only reduce the radial height size of the motor, but also provide a larger winding space for the winding, increase the number of coil turns, improve the motor thrust ratio, and achieve a large cooling capacity refrigeration performance under a small-sized compressor.

[0011] The magnetic tile 21 is a short magnetic steel structure, with an axial length smaller than the left and right outer soft magnets 12, and is made of NdFeB material with excellent magnetic properties, and is evenly glued to the cylindrical surface of the outer bracket of the compression piston 22 to form the motor mover component 2. The "C"-shaped motor structure can ensure uniform motor magnetic circuit, less end leakage, large specific thrust, and high motor efficiency.

[0012] The columnar machine spring 31 is a double-helix or single-helix linear column spring with a rectangular cross-section, with a screw hole in the axial direction of the end and a pin hole in the radial cylindrical surface of the tail. The columnar machine spring 31 serves as a supporting structure for the mover component 2. The mover component 2 is threadedly connected to one end of the columnar machine spring 31 by a piston screw 32, and the other end is connected to the sealing end cover 34 by a spring pin 33 (laser spot welding is used to reinforce the connection end surface between the spring pin 33 and the sealing end cover 34 to further improve the strength of the supporting structure). The columnar machine spring 31 is machined and formed with high-strength spring steel material, with high structural strength and strong environmental adaptability. The supporting structure has a small number of parts and a simple structure, which greatly reduces the axial length and radial height of the compressor.

[0013] When an alternating current is passed through the motor winding 13, a motor magnetic circuit is formed in the motor stator component 1, providing an electromagnetic thrust for axial reciprocating motion to the magnetic shoe 21, thereby driving the compression piston 22 in the moving component 2 to move in the compression cylinder 4. The reciprocating motion forms an alternating pressure wave, which is finally transmitted to the expander end of the refrigerator, pushing the displacer to expand and do work to produce a refrigeration effect. Among them, the columnar machine spring 31 not only provides axial stiffness for the moving component, but also provides it with flexible and adjustable radial support, effectively reducing the wear on the piston surface and improving reliability.

[0014] The present invention greatly reduces the axial and radial dimensions of the linear compressor through a "C"-shaped motor structure and a high-strength rectangular-section cylindrical machine-added spring, thereby achieving a small and lightweight compressor with a large cooling capacity. The compressor can be applied to refrigeration equipment with high requirements on reliability and environmental adaptability and limited placement space.

[0015] A linear compressor using a lightweight linear motor comprises a stator component 1, a mover component 2, a mover support structure 3 and a compression cylinder 4 of the linear motor.

[0016] The linear compressor structure is a single-piston linear compressor with a "C"-shaped motor structure. According to the cooling capacity requirements of different application scenarios, the size of individual parts in the motor component or the mover support structure component can be quickly matched and adjusted, such as changing the wire diameter and number of turns of the motor winding 13 to adjust the motor specific thrust; changing the cross-sectional aspect ratio of the columnar machine spring 31 to adjust the diameter / axis stiffness ratio of the mover component. In addition, the columnar machine spring 31 can be "T"-shaped, and the inner hole surface of the tail adopts a threaded structure, which is threadedly connected to the sealing end cover 34. The single-piston linear compressor in this embodiment has the characteristics of simple structure, convenient parameter adjustment, and high maintainability.

[0017] A lightweight linear motor and a linear compressor provided by the present invention have the following advantages:

[0018] (1) The "C"-shaped linear motor provided by the present invention has a simple structure, a uniform magnetic circuit, high motor efficiency, and can significantly reduce the size of the compressor, improve specific thrust, and achieve small size, light weight, and high refrigeration performance;

[0019] (2) The machined spring provided by the present invention has a simple design and high structural strength, and can realize radial flexible self-adjustment of the compression piston;

[0020] (3) The linear compressor provided by the present invention has a small number of components, a simple structure, low assembly difficulty, and a high yield rate, which significantly improves the consistency of the refrigeration performance of the refrigerator, reduces production costs, and is conducive to mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of a linear motor and a linear compressor of the prior art;

[0022] Figure 2 It is a schematic diagram of the supporting structure of the motor mover component in the prior art;

[0023] Figure 3 is a schematic diagram of a linear compressor using a lightweight linear motor according to the present invention;

[0024] Figure 4 It is a detailed structural diagram of the lightweight linear motor component in the present invention;

[0025] Figure 5 It is a detailed structural diagram of the machined spring in the present invention;

[0026] Figure 6 It is a single piston linear compressor with a "C" shaped motor structure in the present invention.

[0027] In the figure:

[0028] 1 is the stator component of the linear motor, 2 is the mover component of the linear motor, 3 is the mover support structure, and 4 is the compression cylinder;

[0029] 11 is the upper outer soft magnet, 12 is the left and right outer soft magnet, 13 is the motor winding, 14 is the inner soft magnet, 21 is the magnetic tile, 22 is the compression piston, 31 is the columnar machine spring, 32 is the piston screw, 33 is the spring pin, and 34 is the sealing end cover. DETAILED DESCRIPTION

[0030] In order to make the purpose, content, and advantages of the present invention more clear, the specific structure and working principle of the present invention are further described in detail below in conjunction with the accompanying drawings and embodiments.

[0031] Example 1

[0032] like Figure 3 , Figure 4 and Figure 5 As shown, the lightweight linear motor and linear compressor of the present invention include:

[0033] First, the annular upper outer soft magnet 11, the left and right outer soft magnets 12 with a C-shaped cross section, and the annular inner soft magnet 14 together constitute the "C"-shaped motor stator component 1 structure. Among them, the left and right outer soft magnets 12 are axially symmetrical structures, and the radial end faces are provided with winding wire grooves to facilitate the motor lead-out. The cylindrical surface of the inner soft magnet 14 is cut with a number of straight line grooves along the axial direction, and the wire grooves are evenly arranged, which can effectively reduce the eddy current loss in the motor magnetic circuit. The cavity surrounded by the upper outer soft magnet 11 and the left and right outer soft magnets 12 is the placement space for the motor winding 13. Compared with the traditional structure, it is an external coil. Its long rectangular cavity structure can not only reduce the radial height of the motor, but also provide a larger winding space for the winding, increase the number of coil turns, improve the motor specific thrust, and achieve a large cooling capacity refrigeration performance under a small-sized compressor. The magnetic shoe 21 is a short magnetic steel structure, with an axial length smaller than the left and right outer soft magnets 12. It is made of NdFeB material with excellent magnetic properties and is evenly glued to the cylindrical surface of the outer bracket of the compression piston 22 to form the motor mover component 2. The "C"-shaped motor structure can ensure uniform motor magnetic circuit, less end leakage, large specific thrust, and high motor efficiency.

[0034] Secondly, a high-strength rectangular cross-section cylindrical machine spring 31 is used as the support structure of the mover component 2. The mover component 2 is threadedly connected to one end of the cylindrical machine spring 31 through a piston screw 32, and the other end is connected to the sealing end cover 34 through a spring pin 33. Laser spot welding is used to reinforce the connection end surface of the pin to further improve the strength of the support structure. The support structure has a small number of parts and a simple structure, which greatly reduces the axial length and radial height of the compressor.

[0035] During the assembly process of the linear compressor of the lightweight linear motor, the magnetic tile 21 is evenly arranged on the cylindrical surface of the outer bracket around the axial direction of the compression piston 22, and then the screw through-hole end of the cylindrical machine spring 31 is placed in the inner hole of the compression piston 22, and the piston screw 32 is used for threaded connection. The sealing end cover 34 is placed in the tail inner hole of the cylindrical machine spring 31, and connected with the spring pin 33. The above parts form the motor mover component 2. The two inner soft magnets 14 are respectively inserted into the two ends of the bracket of the compression cylinder 4, which can be connected by gluing or laser welding. The compression pistons 22 in the two groups of motor mover components 2 are symmetrically placed in the inner hole of the compression cylinder 4, and the mating surface of the sealing end cover 34 and the compression cylinder 4 can be connected by laser welding or screws. Then the left and right outer soft magnets 12 are placed on the radial cylindrical surface of the sealing end cover 34, and the two are connected by laser welding. The motor winding 13 is wound in the slots of the left and right outer soft magnets 12, and the upper outer soft magnet 11 is inserted thereon, and the side connection between the left and right outer soft magnets 12 and the upper outer soft magnet 11 is connected by laser welding. The above parts are assembled together to form a linear compressor using a lightweight linear motor in the present invention.

[0036] When an alternating current is passed through the motor winding 13, a motor magnetic circuit is formed in the motor stator component 1, providing an electromagnetic thrust for axial reciprocating motion to the magnetic shoe 21, thereby driving the compression piston 22 in the moving component 2 to move in the compression cylinder 4. The reciprocating motion forms an alternating pressure wave, which is finally transmitted to the expander end of the refrigerator, pushing the displacer to expand and do work to produce a refrigeration effect. Among them, the columnar machine spring 31 not only provides axial stiffness for the moving component, but also provides it with flexible and adjustable radial support, effectively reducing the wear on the piston surface and improving reliability.

[0037] The present invention greatly reduces the axial and radial dimensions of the linear compressor through a "C"-shaped motor structure and a high-strength rectangular-section cylindrical machine-added spring, thereby achieving a small and lightweight compressor with a large cooling capacity. The compressor can be applied to refrigeration equipment with high requirements on reliability and environmental adaptability and limited placement space.

[0038] Example 2

[0039] like Figure 6 As shown, the single-piston linear compressor of the present invention adopts a "C"-shaped motor structure, and can quickly match and adjust the size of individual parts in the motor component or the mover support structure component according to the demand for cooling capacity in different application scenarios, such as changing the wire diameter and number of turns of the motor winding 13 to adjust the motor specific thrust; changing the cross-sectional aspect ratio of the columnar machine spring 31 to adjust the diameter / axis stiffness ratio of the mover component. In addition, the columnar machine spring 31 can be "T"-shaped, and the surface of the inner hole of the tail adopts a threaded structure, which is threadedly connected to the sealing end cover 34. The single-piston linear compressor in this embodiment has the characteristics of simple structure, convenient parameter adjustment, and high maintainability.

Claims

1. A lightweight linear motor, comprising a stator component (1), a mover component (2) and a mover support structure (3), characterized in that: The stator component (1) comprises an upper outer soft magnet (11), left and right outer soft magnets (12), a motor winding (13) and an inner soft magnet (14); the mover component (2) comprises a magnetic tile (21) and a compression piston (22); and the support structure (3) comprises a columnar machine spring (31); wherein: The upper outer soft magnet (11) and the inner soft magnet (14) are in the shape of a ring; the cross-section of the left and right outer soft magnets (12) is in the shape of a C with its opening facing the upper outer soft magnet (11); the upper outer soft magnet (11), the left and right outer soft magnets (12), and the inner soft magnet (14) together form a "C"-shaped stator component (1); the cavity surrounded by the upper outer soft magnet (11) and the left and right outer soft magnets (12) serves as a placement space for the motor winding (13), forming an external coil structure of the stator component (1); The magnetic tile (21) is a short magnetic steel structure, and its axial length is smaller than the left and right outer soft magnets (12). The magnetic tile (21) is located on the cylindrical surface of the outer bracket of the compression piston (22), constituting the motor rotor component (2); The columnar machine spring (31) is a double-helix or single-helix linear column spring with a rectangular cross-section, and is used to support the mover component (2).

2. The lightweight linear motor according to claim 1, characterized in that: The left and right outer soft magnets (12) are of axially symmetrical structure, and the radial end faces are provided with winding wire grooves for motor lead-out.

3. The lightweight linear motor according to claim 1, characterized in that: The cylindrical surface of the inner soft magnet (14) is cut with a plurality of evenly arranged straight line grooves along the axial direction, so as to reduce the eddy current loss in the magnetic circuit of the motor.

4. The lightweight linear motor according to claim 1, characterized in that: The magnetic tile (21) is evenly glued to the cylindrical surface of the outer support of the compression piston (22).

5. The lightweight linear motor according to claim 1, characterized in that: The support structure (3) further comprises a piston screw (32), a spring pin (33) and a sealing end cover (34); The end of the cylindrical machine spring (31) is provided with a screw through hole in the axial direction, and the radial cylindrical surface of the tail is provided with a pin hole; the cylindrical machine spring (31) is threadedly connected to the mover component (2) and one end of the cylindrical machine spring (31) through a piston screw (32), and the other end is connected to the sealing end cover (34) through a spring pin (33).

6. The lightweight linear motor according to claim 5, characterized in that: Laser spot welding is used to reinforce the connection end surface between the spring pin (33) and the sealing end cover (34).

7. The lightweight linear motor according to any one of claims 1 to 6, characterized in that: The cross-sectional aspect ratio of the columnar machine spring (31) can be adjusted according to different diameter / axis stiffness requirements.

8. The lightweight linear motor according to any one of claims 1 to 6, characterized in that: The columnar machined spring (31) is machined from high-strength spring steel material.

9. The lightweight linear motor according to any one of claims 1 to 6, characterized in that: The magnetic tile (21) is made of neodymium iron boron material.

10. A linear compressor, characterized in that: A lightweight linear motor comprising a method as described in any one of claims 1 to 8, further comprising a compression cylinder (4).

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